The present invention generally relates to an external tutor for the treatment of fractures in the radius distal end, whereby it is possible to effectively treat said fractures without having to puncture the lower radio cubital articulation.
More specifically, the present invention relates to the functional and construction characteristics of a particular external tutor capable of being used as a fastening auxiliary resource during the treatment of the bone fractures mentioned above.
The major advantage of the tutor of the present invention is that it provides the patient's wrist with good postoperative mobility, both for flexion and extension movements, as well as for pronosupination, once the same has been fitted. This allows the patient, for example, to pour water from a receptacle or to drink water from a glass, and to perform these types of movements on a gentle basis. It is evident that it is an early mobility if compared to conventional treatments for the same purpose (plasters, tutors bridging the articulation, etc.) wherein an absolute immobility is required throughout the zone of influence for long periods of time. The characteristic of the tutor of the invention provides the patient with relative comfort throughout the whole therapeutical treatment and also decreases reflex sympathetic phenomena and osteoporosis risks.
Essentially, the invention refers to a monoplanar tutor, the dimensions of which are about 70 mm long per 10 mm wide and 5 mm thick, comprising a planar head articulated to a support body by means of a transverse screw, with respect to which said head may rotate and be fixed in the position chosen by the physician.
The novelty lies in that both the head and the body have transverse orifices run through by longitudinal pins which position the fractured bone portions in the correct place, with the particular feature that, due to the construction design of the tutor, the pins used and the tutor form a triangle which is very stable and safe.
To that effect, the transverse orifices of the articulated head have a 45.degree. inclination with respect to the tutor's axis, while the body preferably has two or three orifices, two of which are perpendicular to the axis and the third one which may have a relative inclination so as to allow the utilization of any additional pin that will support any bone fragment that has remained unfixed by the others. Each of said orifices run through by the faces a perpendicular orifice where there are respective headless fastening screws; said screws exert pressure upon the pins, thus providing a retention action by means of a removable frictional adjustment.
Consequently, in order for the invented tutor to fit the patient, the following must be done: the patient is placed in a dorsal decubitus position, he is anaesthetized and then the "Zockowlosky" apparatus pulls on the limb, a free countertraction is applied from the elbow, using a 5 Kg weight, and this allows to perform manual reduction movements. Subsequently, the first pin is run through, and for that purpose it is convenient to use an image intensifier or Rx controls (which is much more simple than the image intensifier). Consequently, the first pin is put into position in a 45.degree. angle from the radius styloid apophysis; the fracture focus is internally pierced and then it penetrates the internal cortical of the radius proximal end.
Upon the penetration of the first pin, the tutor is mounted and fitted using its distal orifice, so that it will be run through by said pin, leaving the tutor one centimeter away from the user's skin in order to avoid decubitus. Then the second pin is placed, penetrating the most proximal orifice of the tutor's body, which operates as a guide since it is perpendicularly oriented respect to the plate and to the radius.
Once the steps mentioned above have been completed, it is possible to finally fix the tutor using the rest of the passing orifices as a guide for the placement of the remaining pins, which is very simple. If there is a front or a rear fragment or a "Die Punch" fragment, it is reduced and then the remaining orifice in the tutor's body is used to place the sixth pin.
The stable fixing of the tutor is achieved by adjusting every screw facing the orifices through which pins penetrate, and by the transverse screw acting as an axis that articulates the tutor's head, and Rx controls are performed.
The tutor thus described is particularly suited for treating extra-articular fractures as well as non displaced intra-articular fractures.
The above mentioned characteristic pointing out that the tutor's head is articulated to the body thereof, so that it can be turned until adopting the selected position, before being adjusted and fixed, allows pins to be adapted to different orientation angles either towards the radius or away from it.
Once the tutor has been finally mounted, the structure defined in conjunction with the pins has a triangular form which, from a physical and mechanical point of view, is the rigid structure that best tolerates the different mechanical requirements to which it may be subjected.
To complete the advantages briefly described above, and many others that may be conceived by users and people skilled in the art, and to facilitate the understanding of the constructive, constitutive and functional characteristics of the external tutor of the invention, two preferred embodiments schematically illustrated regardless of a specified scale are described below with reference to, on the enclosed drawings. Accordingly, the scope of the present invention should be assessed as that of the appended claims.